**Abstract**

Cork stoppers have been used for many centuries to seal wine in various vessels. Therefore, corks have become a traditional part of wine packaging in many countries and still play an important role for the entire wine industry. Nowadays, there is a wide option of bottle cork stoppers on the market, such as natural corks, agglomerated and technical stoppers (1 + 1), etc. These cork closures have a number of advantages, including positive sustainable and ecological aspects. Natural cork material can also be responsible for *cork taint*, which imparts musty/moldy or wet cardboard off-odors to the wine. However, corks are not the only source of *cork taint* in wine, as will be shown in the present chapter. Over the past decades, a number of compounds have been detected that can contribute to the *cork taint*. Among them, haloanisoles play a major role, in particular 2,4,6-trichloroanisole (TCA), which has been shown to be responsible for 50–80% or more of musty defect cases in wine. Currently, the cork and wine industries have developed a number of tools and technologies to effectively prevent *cork tait* in wine or to remove it if the wine is already contaminated. These practical as well as analytical questions about the TCA defects are the subject of the actual chapter.

**Keywords:** 2,4,6-trichloroanisole (TCA), cork taint, musty, moldy, cork stopper, wine
